found:Work cat.: No, Giseop. An efficient and reliable DDoS attack detection algorithm using a fast entropy computation method, 2009:p. 2 (Denial of service attacks uses multiple systems to attack one or more victim systems with the intent of denying service to legitimate users of the victim systems)
found:Webopedia, Oct. 27, 2009:(DoS attack: Short for denial-of-service attack, a type of attack on a network that is designed to bring the network to its knees by flooding it with useless traffic.)
found:Wikipedia, Oct. 27, 2009:(A denial-of-service attack (DoS attack) or distributed denial-of-service attack (DDoS attack) is an attempt to make a computer resource unavailable to its intended users.)